Ten maize seed lots, representing two cultivars ('AG-401' and 'AG-162') were treated with fungicide + insecticide and stored under normal environmental conditions, during 18 months (from May/1984 to November/1985). The laboratory studies, conducted at three month invervals, consisted of germination, accelerated aging and cold test (with and without the use of soil as substrate); field study comprised seedling field emergence. Results indicated that cold test with the utilization of soil and accelerated aging showed the greatest efficiency for identifying seedling field emergence potential, storability and separation of maize seed lots in different vigor levels. The utilization of a combination of several tests for vigor evaluation is a fundamental procedure to be done before seed storage.